Articles of footwear can include an upper and a sole assembly. The upper can include layers or sections of material that wrap about and cover a substantial portion of the wearer's foot and ankle. The upper can also include laces, straps, or the like for securing the footwear to the wearer's foot. The sole assembly can include an outsole and a midsole. The outsole can be a unitary piece of relatively high-friction material that provides traction. The midsole can include foam that is disposed between the outsole and the upper for providing cushioned support for the wearer.
In some cases, the article of footwear may not be versatile enough for certain activities. For instance, the midsole may be sufficiently stiff enough to support high impact activities, such as running, but the midsole may be too stiff for walking and/or standing for long periods of time. As such, the footwear may be uncomfortable for certain activities. Also, the midsole may be resilient enough to properly cushion a wearer's feet for long periods of standing; however, the same midsole may be too resilient when pushing off and thrusting the foot forward (e.g., at the start of a sprint). As such, the midsole may deflect too much and excessively absorb the input force from the wearer, thereby reducing the forward thrust of the wearer's foot.
Accordingly, there remains a need for an article of footwear that is more versatile such that the footwear provides adequate support during a wide variety of activities. Also, there remains a need for an article of footwear that can be comfortable enough to wear while walking and standing during long periods of time and that also provides a sufficiently stiff surface for pushing off while thrusting the foot forward.